Transfer device for images by the use of liquid development electrophotography

ABSTRACT

There is disclosed herein a simple and reliable liquid development transfer device for images by the use of liquid development electrophotography.

United States Patent 1191 Suzuki 1 TRANSFER DEVICE FOR IMAGES BY THE USEOF LIQUID DEVELOPMENT ELECTROPHOTOGRAPHY [75] Inventor: Shigeru Suzuki,Yokohama, Japan [73] Assignee: Kabushiki Kaisha Ricoh, Tokyo,

Japan [22] Filed: Dec. 29, 1970 21 Appl. No.: 102,529

Related U.S. Application Data [62] Division of Ser. No. 771,162, Oct.28, 1968, abandoned.

[30] Foreign Application Priority Data Nov. 8, 1967 Japan ..42/7l778 52us. c1 ..l18/637,1l7/37LE,118/258, 11s o1o.23,355/1o 151 1m. c1. ..G03g13/00 [58] Field of Search ..l l8/DIG. 23, 637, 257, 258,

118/259, 222; 117/175, 37 LE; 96/l.4; 355/10 1111 3,720,183 1 51Marh 13,1973 [56] References Cited UNITED STATES PATENTS 3,281,241 10/1966Mihajlov ..96/l 3,120,446 2/1964 Hunter ..1 17/1 7.5 3,372,027 3/1968Gnndlach et a1. ..96/l 3,596,635 8/1971 Smitzer ..1 18/637 3,202,5268/1965 Ostensen. ..1 18/637 2,951,443 9/1960 Byrne 1 01/426 3,556,7841/1971 Robinson et al ..96/1 .4 2,565,370 8/1951 Hodin ..9 l /49 PrimaryExaminer-Mervin Stein Assistant Examiner-Leo Millstein Attorney-Waters,Roditi, Schwartz & Nissen [57] ABSTRACT There is disclosed herein asimple and reliable liquid development transfer device for images by theuse of liquid development electrophotography.

- 5 Claims, 3 Drawing Figures TRANSFER DEVICE FOR IMAGES BY THE USE OFLIQUID DEVELOPMENT ELECTROPHOTOGRAPIIY This application is a divisionalapplication based on my earlier filed application Ser. No. 771,162 filedOct. 28, 1968, formerly copending but now abandoned.

The present invention relates to transfer devices for images by the useof liquid development electrophotography.

Since the copy paper on which an image is to be made by liquiddevelopment electrophotography is generally opaque, it cannot be used asan original for a copying apparatus such as a diazo-type copyingapparatus, in which transparency of the original paper is required. 7

A liquid development electrophotographic copy paper for an or a secondoriginal has already been used in practice. However, since the use ofZnO in the paper cannot be avoided and this paper absorbs ultravioletrays the copy speed is slow and the sharpness of the image is notsufficient for practical use.

It is an object of the invention to get rid the abovementioned defects.

It is another object of the invention to provide a simple and reliabledevice to transfer an image by means of liquid developmentelectrophotography.

With these and other objects in view, the invention will be nextexplained in connection with the accompanying drawings, wherein:

FIG. 1 is a diagrammatic elevation view of apparatus to show theprinciple of transfer according to the present invention;

FIG. 2 is a longitudinal cross sectional view through a transfer deviceaccording to one embodiment of the present invention; and

FIG. 3 is a fragmentary plan view of feed tables for paper to betransferred and transfer paper.

In FIG. 1, is a paper 1 to be transferred, for example, an image 2formed by a positive toner which is to be copied by liquid developmentelectrophotography. Copy paper 3 is made of transparent paper such astracing paper and others the like. The paper (recording material) to betransferred (i.e., having an image to be transferred) and the copy paper(image receiving material) 3 are fed in convergently so as to provide anintimately close gap between them, and a wetting liquid .4 with anappropriate volatility is introduced into the gap between the papers.The toner'on the transfer paper 3 is wetted and softened and thenswells. The transfer paper 3 is shifted to a gap between coronadischarge electrodes and subjected to a corona discharge from the sideof the transfer paper, the toner is transferred to the transfer paperand thereby the image is transferred. The corona discharge is formedbetween a grounded conductive ro'ller acting as an electrode and anopposed electrode positioned at a .predetermined distance above theroller.

In the following, the structure and the operation of the main parts of atransfer device according to the invention will be explained referringto FIG. 2. When a mainswitch 5 is turned on, a main motor 6 starts torotate, and guide rollers 10 and 11 rotate in the direction shown by thearrowsbeing driven by sprocket wheels 7 and 8 and a chain 9. A pulley 14is also rotated by a pulley 12 which is integral-with and coaxiallyfixed to the sprocket wheel 8 and acts through a round belt 13.

On the front side of the pulley 14 in FlG. 2, a cam 15 is supportedcoaxially and both are connected through a one revolution clutch. When astart button 16 is pushed, a lever 17, a paper stopper 18, a lever 19and a lever 20 rotate clockwise around a shaft 21 and undergodisplacement from the position depicted shown in broken lines to that bysolid lines. These rotating members have a tendency to rotatecounterclockwise through the action of a spring 24 which is stretchedbetween a pin 22 at the end of the lever 17 and another pin 23 mountedon a fixed part of the machine.

There is provided a cam follower 25 adjacent the lever 17. When the camfollower 25 falls into a recess 26 of the cam 15, the cam 15 stopsrotating. However, the cam 15 rotates when the cam follower 25 is out ofthe recess 26 and slides around the external periphery of the cam 15.

When the lever 19 is at the position shown in broken lines, it pushes upboth ends of the shaft 28 of an upper feed roller 27 so that the upperfeed roller 27 is at the position shown in broken lines. Under theseconditions, there is a wide gap between the guide roller 11 and theupper feed roller 27. When the paper stopper 17 is at the position shownby the broken lines, the tips of the paper to be transferred on a feedtable 29 and of the transfer paper on a feed table 30 strike the stopper18, and the positioning of both papers with each other is effective.When the lever 20 comes to the position shown by solid lines, the'buttonof a switch 31 for a corona discharger 32 is pushed, and the circuit forthe corona discharger 32 is closed.

When the main switch 5 is turned on, a pumping motor 33 starts torotate. A wetting liquid 38 is poured into a tank 37 through an opening36 of a pipe 35 by means of a pump 34. If the paper to be transferredand the transfer paper are placed on the feed tables 29 and 30,respectively, the wetting liquid is fed between the paper to betransferred and the transfer paper, and the toner which forms the imageon the paper to be transferred is wetted, softened and swells to someextent.

When the start button 16 is pushed, each rotating member shifts to theposition shown in solid lines around the shaft 21 as a center asdescribed above cam follower 25 comes out of the recess 26 of the cam 15and the cam 15 starts to rotate. The cam follower 25 slides on theexternal periphery of the cam 15 and each rotating member remains in theposition shown in solid lines. When the paper stopper 18 rotates andshifts to the position shown in solid lines, it becomes possible to feedin the paper to be transferred and the transfer paper as the lever 19rotates to the position shown by a solid line, the upper feed roller 27comes down and displaces the paper to be transferred and the transferpaper keeping them between the upper feed roller 27 and the guide roller11 as shown in FIG. 1.

The paper to be transferred and the transfer paper receive a coronadischarge while on their way, and pass between guide rollers 10 and 39.The image is then transferred as explained with above reference toFIG. 1. Though not shown, the paper carrying the image to be transferredand the transfer paper are separated by a separating means, and ifnecessary, they are heated to be dried. Element 40 is a grounded rollerfor the corona discharge, and element 41 is a high-voltage power supplyfor the corona discharge.

When the cam makes one rotation, the cam follower 25 of the lever 17falls into the recess 26 of its cam 15, and each rotating member comesback to the original position following the stopping of the cam 15.

An indication lamp 42 is lighted when the main switch is turned on.

The feed tables 29 and 30, upon which the paper 'to be transferred andthe transfer paper are to be placed are respectively inclined downwardlyand forwardly and their forward ends have comb shapes as shown in FIG.3. Therefore, it is possible to see through them. At the same time, thewetting liquid flows down without dispersing on the tables more than isneeded.

The invention as explained above in detail, has the following remarkableeffects:

1. An image formed by a liquid development electrophotographic copy canbe transferred upon a highly transparent paper by simple means.

2. Since a wetting liquid is poured into the gap between the paper to betransferred and the transfer paper, only one side of each paper becomeswet while the other side is dry, so that both papers are scarcelydamaged, easily dried, and convenient to carry.

3. Since the toner is transferred onto the transfer paper through coronadischarge, the transferred image becomes uniform.

4. When a paper to be transferred and a transfer paper corona discharge,they have a tendency to stick to the opposite electrodes, so that whenthe transfer is conducted while the transfer paper is moving on. It isnecessary to eliminate this tendency to stick to the oppositeelectrodes, and for that purpose, the metal roller is used in theinvention.

5. Each of the feed tables for a paper to be transferred and a transferpaper has a forward end formed in the comb shape so as to enable easilyviewing things underneath through the comb-shaped end, and it also makesthe wetting liquid flow downward without dispersing on the tables in anamount more than is needed.

While the present invention has been particularly described in terms ofa specific embodiment thereof, it will be understood that numerousdeviations and modifications may be readily devised by those skilled inthe art without departing from the scope of the invention.

What is claimed is:

1. A device for transferring a toner image from a recording material toan overlaying image receiving material by wetting the toner image andapplying a corona discharge electric field, said device comprisingseparate slide-in channels for the recording material and the imagereceiving material which are guided into superposed relationship, aplurality of pairs of feed rollers defining a feed path for saidmaterials, corona discharge means for producing a corona dischargenormal to the surface of the superposed recording and image receivingmaterials, said channels including said one pair of said feed rollersbeing positioned in continuation of two vertically spaced, downwardlyinclined and converging supporting plates for the sliding in of therecording and image receiving materials, a wetting agent feed pipehaving an o ening arranged between said plates, one roller of sal onepart being pivotally mounted, a pivotally mounted lever for pivoting oneroller of said one pair to open a roller gap, and an arm attached tosaid lever for closing the feed path.

2. A device as claimed in claim 1 comprising a motor for driving atleast some of said rollers, a cam driven by said motor and a camfollower attached to said lever and cooperating with the cam todetermine a transfer cycle.

3. A device as claimed in claim 1 comprising a reservoir for saidwetting agent and a pump for pumping said agent through said pipe.

4. A device as claimed in claim 1 comprising a switch for controllingsaid corona discharge means and means attached to said lever foroperating said switch.

5. A device as claimed in claim 1 wherein said plates includecomb-shaped edges.

1. A device for transferring a toner image from a recording material toan overlaying image receiving material by wetting the toner image andapplying a corona discharge electric field, said device comprisingseparate slide-in channels for the recording material and the imagereceiving material which are guided into superposed relationship, aplurality of pairs of feed rollers defining a feed path for saidmaterials, corona discharge means for producing a corona dischargenormal to the surface of the superposed recording and image receivingmaterials, said channels including said one pair of said feed rollersbeing positioned in continuation of two vertically spaced, downwardlyinclined and converging supporting plates for the sliding in of therecording and image receiving materials, a wetting agent feed pipehaving an opening arranged between said plates, one roller of said onepair being pivotally mounted, a pivotally mounted lever for pivoting oneroller of said one pair to open a roller gap, and an arm attached tosaid lever for closing the feed path.
 1. A device for transferring atoner image from a recording material to an overlaying image receivingmaterial by wetting the toner image and applying a corona dischargeelectric field, said device comprising separate slide-in channels forthe recording material and the image receiving material which are guidedinto superposed relationship, a plurality of pairs of feed rollersdefining a feed path for said materials, corona discharge means forproducing a corona discharge normal to the surface of the superposedrecording and image receiving materials, said channels including saidone pair of said feed rollers being positioned in continuation of twovertically spaced, downwardly inclined and converging supporting platesfor the sliding in of the recording and image receiving materials, awetting agent feed pipe having an opening arranged between said plates,one roller of said one pair being pivotally mounted, a pivotally mountedlever for pivoting one roller of said one pair to open a roller gap, andan arm attached to said lever for closing the feed path.
 2. A device asclaimed in claim 1 comprising a motor for driving at least some of saidrollers, a cam driven by said motor and a cam follower attached to saidlever and cooperating with the cam to determine a transfer cycle.
 3. Adevice as claimed in claim 1 comprising a reservoir for said wettingagent and a pump for pumping said agent through said pipe.
 4. A deviceas claimed in claim 1 comprising a switch for controlling said coronadischarge means and means attached to said lever for operating saidswitch.